The present invention relates to a steering wheel in particular for a motor vehicle.
There exists a constant desire to improve the safety of motor vehicle users.
For example, motor vehicles are equipped with various means for absorbing as far as possible the kinetic energy of the body of the users in the event of impact so as to avoid serious body injury.
The driver of the vehicle is particularly exposed to this type of problem owing to the presence of the steering wheel which might cause relatively considerable damage.
There have therefore been developed in the prior art various devices whereby either the steering wheel or the steering column itself deforms for absorbing the shock.
Thus, for example, an arrangement is known from the European Pat. No. 0 130 009 for absorbing energy, for example in a motor vehicle steering column, this column having two telescopic parts which are maintained in position by a deformable sleeve which deforms in the event of impact and permits one of the parts of the steering column to slide in the other part and thus absorb a part of the impact energy.
A safety steering column for a motor vehicle is also known from the document FR-2 244 658 (corresponding to U.S. Pat. No. 3,934,987) which comprises a steering shaft which is permanently deformable under the action of the forces applied when absorbing energy and is provided with means which produce, for a given critical load, a deformation of the steering shaft. The steering shaft is shaped, at least in one region, in the known manner in the form of a helix whose coils have a diameter which is distinctly larger than the diameter of the non-deformed part of the steering shaft.
The document FR-2 254 960 also discloses a safety steering wheel whose frame comprises, welded on each side of a central hub, two steel branches which are bent substantially in the shape of an S in the vicinity of their end welded to the hub, and are welded at their other end to the steel frame ring of the steering wheel, said branches subtending an angle at the centre in the neighbourhood of 30.degree..
However, all of these devices have a number of drawbacks, in particular as concerns their structure and their utilization in a motor vehicle.